Related by context. Frequent words. (Click for all words.) 55 fracturing fluids 51 frac fluid 50 combustion gases 50 CO -2 50 hydrothermal fluids 50 carbon dioxide CO2 50 sediment 50 groundwater aquifers 50 flyash 49 CO2 49 methane 49 kerogen 49 gaseous hydrogen 48 methane hydrate 48 insitu 48 argon gas 48 flammable vapor 48 flammable gases 48 shallow aquifer 48 Hydrogen sulfide 48 Sediment 47 evaporation ponds 47 containments 47 pentane 47 carbon dioxide 47 hydrofluoric acid 47 desorption 47 slurry 47 NH3 47 Hydrochloric acid 47 Glycol 47 potassium permanganate 47 nitrogen 47 wellbores 47 flue gases 47 nitrification 47 calcium sulfate 47 atmospheric nitrogen 47 tailing ponds 46 methane hydrates 46 sequester carbon dioxide 46 Sulfuric acid 46 reservoir 46 corrosive acid 46 BTEX 46 radioactive contaminants 46 dissolved solids 46 benzene toluene 46 clathrates 46 ammonia nitrogen 46 silt 46 drainage basins 46 metal hydride 46 flammable vapors 46 oily residue 45 coffer dam 45 combustible gases 45 drywell 45 CO2 sequestration 45 unburned fuel 45 Asbestos fibers 45 dewatered 45 diatomite 45 elemental sulfur 45 Aquifers 45 phosphine 45 overpressure 45 groundwater extraction 45 fracking fluids 45 Sediments 45 hydrogeologic 45 potent greenhouse gas 45 adsorbent 45 ammonia 45 groundwater 45 bile acid 44 sulphates 44 fluorocarbons 44 Seepage 44 borate 44 evaporative 44 airborne particulates 44 wastewater effluent 44 radioactive material 44 Turbidity 44 DBPs 44 absorbs carbon dioxide 44 oil sheens 44 gas hydrates 44 feedwater 44 hypochlorite 44 atmospheric pollutants 44 leachate 44 cofferdam 44 chlorides 44 sumps 44 subsurface 44 recharge groundwater 44 sorption 44 settling ponds 44 Carbon sequestration